Electrostatic separator for sorting out the constituent parts of commodities according to their permeability.



Witnesses:

' A. BIBOLINI & P/RIBQNI. I ELECTROSTATIC SEPARATOR-FOR SORTING OUT THE CQNSTITUENT PARTS QF COMMODITIES I ACCORDING TO THEIR PERMEABILITY.

AtPLICATlOH FILED Arnie; 19:4. I

Patented Sept. 28, 1915.

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mievzetsei A. BIBOLINI & P. RIBONI. ELECTROSTATIC'SEPARATOR FOR SORTING OUT THE CONSTITUENT PARTS OF COMMODITIES ACCORDING TO THEIR PERMEABILITY.

I APPLlCATlON FILED APR- 25. I914.

1,15%907. PatentedSept. 28, 1915.

'2 SHEETS-SHEET 2.

ALDO BIBOLINI, 0F AGORDO, AND PIETRO RIBONI, OF NAPLES, ITALY.

ELECTROSTATIC SEPARATOR FOR SORTING OUT THE'CONSTITUENT PARTS'OF COMMODITIES ACCORDING TO THEIR PERMEABILITY.

Specification of Letters Patent.

Patented Sept. 28, 1915.

Application filed April 25, 1914. Serial No. 834,428.

To all whom it may concern.

Be it known that we, ALoo BIBOLINI and lPmrRo RIBoNI, engineers, subjects of the King of Italy, residing, respectively, at Agordo, Province of Belluno, Italy, and at Naples, Italy, have invented certain new and useful improvements in or relating to electrostatic separators for sorting out the constituent parts of commodities according to their permeability, of which the following is a specification.

his invention relates to improvements in connection with electrostatic separators for sorting out the constituent parts of commodities according to their permeability.

Separators of the above type are already known in which a commodity is carried by 21% ilign-electrifiable conveyer into an electric According to the present invention there is provided above a badly conducting c0nveyer a pole or field plate the face of which rises toward both sides transversely to the direction of movement while its length corresponds to about the distance between the feeding and the discharging devices. The grains in passing through the electric field move to and fro between the conveyer and the face of the pole or field plate. As a re sult of the laterally curved form of the face of the pole or field plate the grains during their to and fro movements become gradually sorted out in such a manner that all grains possessing a higher permeability become removed from the zone of feed in a transverse direction to that of the movement of the conveyer, whereas all grains possessed. Owing to the peculiar formation of the pole or field plate each grain makes a large number of movements toward the superposed pole or field within the zone of fe .plate and back again to the conveyer band,

the band is traveling at a ample in the accompanying drawings, in

which Z.

Figure 1 is a diagrammatic view illustrating the electrostatic field. Fig. 2 is a crossmg a lower degree of permeability remain this manner a very exact slight variation in section on the line M-N of Fig. 3 which shows the apparatus in side elevation. Fig. 4 is a plan. Figs. 5 and 6 illustrate diagrammatically the to and fro movements of the grainsbetween pole andconveyer.

Referring to the drawings; on a frame a is secured, by means of a support Z, the upper pole piece or field plate a, which can be charged by suitable means, While the lower pole or field plate .15 is carried by transverse supports 79. The face of the upper pole or field plate 8 inclines, transversely to the direction of movement of the conveyer, upwardly toward both sides. As exemplified in the construction shown, the inclined face of the pole or field plate can have a curved form although other forms may be adopted, say a shallow V shaped form. The lower plane pole face or field plate t is either connected to earth as shown in Fig. 3 (by plate 1?) or is of opposite electrification to that of the upper pole or field plate 8.

As shown in Fig. 3 the face of the pole or field plate 8 extends abovea conveyer band I) for a distance corresponding approximately to the distance between the conveyer drums r and g. The band I), on being moved by the drums r and 9, travels above and in close proximity to the face of the lower pole or field plate t and Within the electric field f. A feed hopper a serves for delivering the commodity upon the conveyer band I). A container d provided with division walls receives the sorted 'commodity.

As shown in Figs. 1 and 2 the inclination transversely of the pole face 8, that is to .say in the present instance, the curvature,

arms m capable of adjustment transversely of the apparatus. The arms m are held in the'adjusted position by set-screws n (see Fig. 1). Further, the position of the pole face 8 with respect to the conveyer band I) can be varied by raising or lowering the two ends of the pole for an equal or an unequal distance through the medium of adjusting devices. As shown the adjusting devices each comprises'a handwheel g actuating, by means of a pair of bevel wheels in, a screwthreaded spindle i passing through a nut I: in the pole-support Z, i

The mode of operation of the separator is field plate .9 in a line as follows :The movement of a grain of dielectric substance carried on the conveyer band I) in being attracted by the pole or of force, becomes accelerated. The grain face of the pole nearly at right angles with some .force and is thereupon thrown back partly by reason of electric repulsion and partly owing to a rebound. The resultof the repulsion is that the grain does not return to the position w on the conveyer band I) from where it started, but drops on to a point y, at a greater distance from the longitudinal axis of the electrostatic field. As a result of the lateral deviating effect of the concussion, an impact angle is formed at y, to which a symmetrical re ound angle corresponds, so that the grain becomes again attracted along a more distant line of force again permeability to a field to the pole face or it is returned to a more distant point on the conveyer band to be attracted in the same manner and again returned to a still more distant point 3 until it is finally returned to a point 3 for example. gether at points on (Fig. 6), the one possessing a greater degree of electrical permeability will return to the conveyer band at a point, for example .2 at a greater distance from the axis of the electrostatic field than the point, for example a, to which the other grain possessing a lesser degree of permeability will return. Thus, given substances of varying permeability located in the central zone of the electrostatic field, the deviation transversely will be greatest in the case of grains possessing a meability, whereby the grains possessing a lower degree of permeability remain nearer the central zone, while the grains possessing higher degree will become transferred to the adjacent outer zones.

As illustrated by dotted lines 'in Fig. & the commodity is distributed from the hopper a. over theconveyer band so as to occupy approximately a central third portion of the width of the band. The commodity,

in the electrostatic field plate 3 whence as it travels beneath the pole face or field plate 8, becomes gradually separated out in the manner above described, so that the grains having the lowest degree of permeability become located in the central zone u of the conveyer ing a higher degree of permeability become located in the zones 1) and w on either side of the central zone u. The thick dotted lines on the left hand' of Fig. 4 indicate imaginary limits of the zones while the fine dotted lines indicate themoving grains. The three divisions of the 7 container d receive the grains as they leave the band from the several zones.

There are three means of suiting the effect of the process to the substances for treattherefore strikes thesaid drums, Of two grams, lylng close to-,

higher degree of per-' band, while the grainshavfield plate 8 can be varied while the apparatus is working; further, the speed of the conveyer band I) can be increased or reduced according to the extent of the relative variation in degree of permeability possessed by the constituent parts of the commodity to be treated; and finally the pole face or field plate 8 can be raised or lowered parallel to, or at an angle with, the conveyer band, in order to strengthen or weaken the efi'ect of the electrostatic field, with, respect to the direction of movement, upon the grains which endeavor to remain in the central zone of the field.

Having now particularly described and ascertained the nature of our said invention, and in what manner the same is to b'e performed, we declare that what we claim is 1. In an electrostatic separator for sorting out the constituent parts of a commodity according to their permeability a frame, conveyer drums sup orted by said frame, a badly conducting conveyer supported by a field plate arranged on the frame and above said conveyer, the surface of said field plate being inclined upwardly toward both sides transversely to the direction of the conveyer travel, the length of said field plate corresponding approximately to the distance between said conveyer drums.

2. In an electrostatic separator for sorting out the constituent parts of a commodity according to their permeability a frame, conveyer drums supported by said frame, a badly conducting conveyer supported by said drums, a field plate arranged on the frame and above said conveyer, the

surface of said field plate being curved uplength of said field plate corresponding apv proximately to conveyer drums.

3. In an electrostatic separator for sorting out the the distance between said constituent parts of a commodity according to their permeability a frame, conveyer drums supported by said frame, a badly conducting conveyer supported by said drums, a field plate arranged on the frame and above said conveyer, the surface of said field platebeing curved upwardly toward both sides transversely to the direction of the conveyer travel, said plate being constituted by a flexible plate carried at its longitudinal edges by arms, said arms being arranged, adjustably on a support extending transversely to the longi-' tudinal axis of the apparatus, the length of said field plate corresponding approximately to the distance between said conveyer drums. I v

14. In-an electrostatic separator for 'sorting out the constituent parts of a commodity according to their permeability a frame, conveyer drums supported by said frame,'a badly conducting conveyer supported by said drums, a field plate arranged on a support above the conveyer, said support having a nut at both ends, vertical screw-threaded spindles passing through said nuts and arranged on the frame of the separator, bevel gears arranged on said spindles and meshing with other bevel gears on horizontal adjusting shafts having hand wheels, the surface of said field plate being inclined upwardly toward both sides transversely to the direction of the conveyer travel, the length of said field plate corresponding approximately to the distance between said conveyer drums.

In an electrostatic separator for sorting out the constituent parts of a commodity according to their permeability a frame, conveyer drums supported by said frame, a badly conducting conveyer supported by said drums, a field plate arranged on a support above theconveyer, said support having a nut at both ends, vertical screw-threaded spindles passing through said nuts and arranged on the frame of the separator, bevel gears arranged on said spindles and meshing with other bevel gears on horizontal adjusting shafts having hand wheels, the surface of said field plate being curved upwardly toward both sides transversely to the direction of the conveyer travel, the length of said field plate correspending approximately to the distance between said conveyer drums.

(i. In an electrostatic separator for sorting out the constituent parts of a commodity according to their permeability a frame, conveyer drums supported by said frame, a badly conducting conveyer supported by said drums. a field plate arranged on a support above the conveyer, said support having a nut at both ends, vertical screw-threaded spindles passing through said nuts and arranged on the frameo-f the separator, bevel gears arranged on said spindlesand meshing with other bevel gears on horizontal adjusting shafts having hand wheels, the surface of said field plate being curved upwardly toward both sides transversely to the direction of the conveyer travel, the length of said field plate corresponding approximately to the distance between said conveyer drums, said plate being constituted by a flexible plate carried at its longitudinal edges by arms, said arms being arranged adj ustably on a support extending transversely to the longitudinal axis of the apparatus.

In testimony whereof we have hereunto set our hands in presence of two subscribing witnesses.

v ALDO BIBOLINI. PIETRO RIBON I. \Vitnesses \VM. A. Nnwcoiw, J. J. WALsHE. 

